Final rails to turn on, managed by a dedicated multi-phase PWM controller. 2. Highly Common Failure Points on the LA-D711P
To work with these files and perform repairs, you will need the right tools. For schematic viewing, you can use a standard (like Adobe Acrobat or Foxit Reader) to view the circuit diagrams. BoardViewer is a popular, free tool for viewing .fz , .brd , and .bv boardview files, while OpenBoardView is a recommended open-source alternative that supports various boardview formats. Some manufacturers also use proprietary formats like Allegro Free Physical Viewer (for .brd files).
The +B rail feeds the Always-On power controller IC (often a Richtek or Texas Instruments multi-rail buck controller). This IC yields at PL7 and +5VALW at PL8 . Without these stable voltages, the ENE KB9022Q Super I/O chip cannot boot, and the laptop will remain entirely dead. Step 3: EC Awake & Power Button Trigger
Input MOSFETs shorting, causing a dead short on the 19V line. PUW1: Charger IC failure. BIOS IC (U34/U35): Frequently requires reprogramming. bdl51 lad711p rev 30 schematic work
Locate the inductor coils for the 3.3V and 5V system regulators ( PL8 for +3VALW and PL9 for +5VALW).
Integrated AMD APUs, such as the AMD A6-7310 or E2-7110.
Powers the Super I/O (EC) chip, the BIOS IC ( U2 ), and the power button circuitry. Without this rail, the laptop will appear completely dead. Final rails to turn on, managed by a
Using the exact Compal schematic allows you to identify component designators (e.g., PU301 , PQ302 , PL302 ) to accurately locate test points on the physical PCB layer, making repair practical and precise.
Before applying power, visually inspect the board under a microscope for signs of liquid ingress, burnt components, or cracked solder joints. Set your digital multimeter (DMM) to . Place the red probe on a verified chassis ground point.
: Detailed repair discussions and requests for this board are active on Notebook1 Forum Forum ELVIKOM Resource Archives For schematic viewing, you can use a standard
Controlled by a dual-channel synchronous buck controller (frequently an RT8243 or similar IC, labeled as PU2 ), these rails must activate as soon as the adapter is connected.
I'll need to cite sources for the information. The search results provide some forum discussions and product listings.
Checks for stable adapter voltage.
Even a hand-drawn functional schematic is better than nothing. You can then digitize it using KiCad or EAGLE for future repairs.
